Pneumatic action for player pianos



Sept. 2, 1924.

G. FREUND PNEUMATIC ACTION FOR PLAYER PIANOS Filed arch l2 .v

A m M11/1111111111;

ZMp/u V,

1 MW I Patented Sept. 2, 1924,

PATENT OFFICE.

GUILLERMO FREUND, OF LIMA., PERU.

PNEUMATIC ACTION FOR PLAYER PIANOS.

Application filed March 12, 1923. Serial No. 624,616.

To all whom @'25 may concern.'

Be it known that I, GUILLERMO FREUND, citizen of Peru, residing at Lima, Peru, have invented certain new and useiul Improvements in Pneumatic Actions for Player Pianos, of which the following is a speciication.

The present invention relates to pneumatic actions for player pianos; and it proposes certain improvements, notably in the construction oi" thev action chest, and ot the valve action, all as hereinafter fully described.

As is generally known, it has heretofore been customary to construct the action chest of a pneumatic action of wood-usually in the form of a bar or block which is recessed and perforated to produce the exhaust chamber and the various passages and ports communicating therewith; and it has also been usual to construct the valve boxes ot wood and separately from the action chest, and then to detachably or otherwise connect the boxes and chest together, the boxes being likewise bored or recessed to form the necessary chambers, passages and ports. lSuch procedure is, of course, expensive; and as the wood is apt to swell and shrink under changing atmospheric and temperature conditions, loose oints frequently result and, on occasions, more or less permanent distortion. According to my invention, however, the use of wood is discarded, and the chest is constructed entirely of metal, preferably in the form oi` two separate main parts which are soldered together; one part constituting the base or bottom of the chest, and the other part the front, rear and top walls. Sheet brass may advantageously be utilized for the construction of both main parts, as well as for the two end walls of the chest, the second or body part being inachine-shaped.

The striker pneuinatics are connected to thev base of the chest, as usual; but the valve boxes, which contain the devices ior controlling these pneumatics, are disposed within the chest and fastened to the base thereof, instead of being arranged in front of the chest, and they are likewise constructed or sheet brass, instead of wood, as heretofore. The valve devices themselves are simplilied, and improved means are pro: vided for mounting them and for eiecting their connection with the tubes leading from the ducts of the tracker.

The accompanying drawings illustrate, by way ot example, one form which the invention may take in practice; and therein:

Figure l is a transverse vertical section of the action;

. Fig. 2 is a horizontal section on line 2 2, Fig. 1;

Fig. 3 is an end view of the chest;

Fig. 4t is a perspective view of one of the valves.

Referring more particularly to the drawings, the improved action chest, as shown, comprises two main parts l and 2, constructed of sheet brass; the body part 1 being bent or shaped by suitable machinery to iorm `the front and rear walls l1 and 12 and the sloping top wall 13, while the base part 2 is merely a liat plate, the two parts being soldered together. The end walls 14 are likewise made of sheet brass and supported upon the base 2, and are soldered thereto and to the edges of the walls 11 and 12 to form an airtight structure, the interior of which is adapted to be connected with the usual vacuum-producing mechanism (not shown) through the intermediary. of the pipe l5 that opens through the bottom of the chest.

In the front wall 1l ot' the chest there is formed a series of openings, corresponding in number to the ducts in the tracker; and in each of these openings there is soldered an iuternally-threaded sleeve 3 which is disposed with its longitudinal axis horizontal.

Each sleeve 3 has an internal circumferential flange 31 at its inner end, against which is clamped, by the action of an externallythreadedk inner sleeve 5, a metal disk ormed on its front face with a centering boss -ll and having' a strip 42 ol" cork or other fibrous material secured to its rear face. .fr metal tube is soldered in an eccentric opening in disk l and projects beyond. the saine at opposite ends, its front portion i3 extending through and beyond the inner clamping sleeve 5 and providing a support to which is connected the adjacent end of the tube 16 leading from the corresponding duct in the tracker (not shown).

The rear portion let of the metal tube extends into the action chest and is provided adjacent its end with au Opening 149, and

beyondk this opening with a plug 17 having a bleed 18 therethrough. The opening 141 is formed in the under side of the tube in" line withxa-n opening 71 formed in the upper wall .of a collapsible diaphragm or pouch 7 whose opposite walls have fibrous disks 6 and (-32 secured to them; the upper disk 6 being also secured to the under side-of the tube portion 14 and havinga central opening 61 which registers with the 'openings 141 and 71, so that communication is thus provided between the tracker duct and the interior of the diaphragm. As a vacuum normally exists in the action' chest, and as the tracker ducts are normally closedto atmospheric air excepting when the perforations inthe note sheet are brought into registration therewith, it will be apparent that the diaphragm or pouch will be normally collapsed, due to its communication with the interior ofv the chest through the bleed 18. But when the tracker ductpis uncovered by a note sheet perforation, then air will pass through the duct andthe tracker 'tube '16 into and through the metal tube Tel-14;, and thencev through the registering openings 111,1, 61, 71 into` the diaphragm- 7, Vwhich will be eX- panded thereby.

The expansion or iniation of the various diaphragms is utilized for the purpose of operating the striker pneumatics 12, of which there is one individual to each tracker duct,

, as usual. The pneumatics have their upper members fixed to the base of the action chest, and their movable lower v'members provided with suitable devices 19 for operative connection with the keyactions, so that when any pneumatic is collapsed, the'movement of its lower member will actuate the corresponding key in the usual way. The operation of the pneumatics for thispurpose isV vcontrolled by the valve mechanisms herein` after described,`which mechanisms, in turn, are controlled by the movements'of the diaphragme or pouches 7.

vAccording to the invention,` each such mechanism or device comprises a box or casing 8 disposed transversely within the action chest and fastened to the bottom wall or base 2 thereof, and having a somewhat elliptical shape. The bottom wall of this ,boxwhicln of course, is formed by the on its upper face, as indicated lat 21, to`pr o vide communication, through the aforesaid cap, between the interior of the box and the atmosphere. In the top of the valve boX, directly op posite the cap 10, there is formed an opening 22 which is also located directly below and in line with the disk 62 on the diaphragm 7. These two openings-i. e., the

:opening 22 and the upper end of the cap lO-are alternately opened and closed by the lower or body port-ion 91 of theV valve 9, which portion is faced at top and bottom with suitable yielding material such as rubber or leather, as shown. The stem portion 92 of the valve projects upwardly through the opening 22` and is of irregular crosssection, for instance stellate or cruc-iform, so as to enable the passage of air through said Vopening while, at the same time, preventing appreciable lateral movement of the valve. In consequence of this construction, the suction created in the action chest by the operation of the pedals will be free to acton the valve, which is thereby raised,

its body portion 91 thus closing opening 22 and shutting ofi' communication between the interior of the chest and the interior of the valve box. The latter, however, is in communication with the atmosphere through the aforesaid opening 22,50 that the striker pneumatic will likewisecommun-icate with the atmosphere through the nipple 11 and, hence, will be in expanded condition.

Then a perforation in the note-sheet is brought opposite the corresponding duct in thc tracker, and yairis admitted to the as sociated diaphragm or pouch 7, then the expansion of the latter will cause its disk 62 to press down the valvewhereby the opening 22 is uncovered and the cap 10 is closed ;k the result being that the vacuum inY the chest is free to act, through the valve boX and the nipple 11, on the pneumatic, which is thereby collapsed and operates the key-action. When the note-sheet `perforation passes beyond the duct, conditions are again reversed and the various parts restoredvto their normal positions.

It will be understood from the foregoing that the inner or clamping sleeves 5 can be readily unscrewed individually from their respective outer sleeves 3, thus releasing the corresponding disks 4: which can thereupon be withdrawn from the action chest through the. said sleeves 8, carrying with them the metal tubes 13-14 and the 'diaphragms or pouches 7. The tracker tubes 16, which are usually liexiblecan, of course, be readily detached from the yfront parts 13 of the metal tubes before the latter are withdrawn from the chest. Hence, ingthe event of any of the above-mentioned parts becoming displaced or injured, it can easily be adjusted or replaced by a new part, ac`

cording as may be necessary. The construction of the chest and valve boxes of metal, rather than of wood, greatly prolongs their effective life and avoids danger of. accidental injury or distortion, as previously explained.

I claim as my invention zl. In a pneumatic action for player pianos and the like, an all-metal actionl chest embodying a flat base plate forming the bottom of the chest, a sheet bent to form the front and rear Walls and the top, and plates forming the end walls, all of said parts being rigidly connected together; and a series of all-metal valve boxes disposed within the chest and mounted on the bottom wall thereof.

2. In a pneumatic action for player pianos and the like, an all-metal action chest; and a series of all-metalvalve boxes disposed within the chest and mounted on the bottom wall thereof.

3. In a pneumatic action for player pianos and the like, the combination of an action chest; a valve box within the chest mounted on the bottom wall thereof and having alining openings in its top and bottom walls which communicate, respectively, with the interior of said chest and with the atmosphere; a striker pneumatic secured to said chest and constantly communicating with the interior of the valve box; a single valve in said box to control both openings and thereby govern communication between the interiors of the box and chest; and atrackercontrolled diaphragm for operating said valve.

et. In a pneumatic action for player pianos and the like, the combination of an action chest; a valve box within the chest mounted on the bottom wall thereof and having alining openings in its top and bottom walls; a striker pneumatic secured to said chest and constantly communicating with the interior of the valve box; a valve in said box to control said openings and thereby govern communication between the interiors of the box and chest, said valve having a stem which projects through the opening in the top wall of the box; a fixed tube mounted in the front wall of the chest and adapted for connection at its front end with a tracker tube; and a collapsible and expansible pouch connected t0 the rear end of the fixed tube immediately above the valve stem to operate the valve consequent upon its expansion.

5. A pneumatic action according to claim 4, in which the fixed tube is provided at its rear end with a plug having a bleed, and is also provided in advance of said plug with an opening registering with a central opening in a disk secured to the upper face of the pouch, said central opening registering with an opening in said pouch face; and in which a second disk is secured to the lower face of the pouch to directly engage and depress the valve stem.

6. In a pneumatic action for player pianos and the like, the combination of an all-metal action chest having a series of internallythreaded sleeves fixed in and opening through its front wall; an externallythreaded clamping sleeve removably engaged in each fixed sleeve; a valve mechanism mounted in said chest in line with each pair of sleeves; and a tracker-'controlled valve-actuating device individual to each valve mechanism removably mounted in each fixed sleeve and clamped in place therein by the corresponding removable sleeve.

7. In a pneumatic action for player pianos and the like, the combination of an all-metal action chest having a, series of internallythreaded sleeves fixed in and opening through its front wall, each sleeve having an inner circumferential flange; a disk disposed within each sleeve against the flange? thereof; an externally-threaded sleeve removably engaged in each fixed sleeve to clamp the corresponding disk in place therein; a valve mechanism mounted in said chest in line with each pair of sleeves; and a trackercontrolled valve-actuating device secured to each disk and removable bodily with the same.

8. In a pneumatic action for player pianos and the like, the combination of an action chest; a valve box having alining openings in its' top and bottom walls which lead directly into the action chest and to the atmosphere, respectively; a striker pneumatic secured t-o said chest and constantly communicating with the interior of the valve box; a single valve in said box to control both openings and thereby govern communication between the interiors of the box and chest; and a tracker-controlled diaphragm for operating said valve.

9. In a pneumatic action for player pianos and the like, the combination of an action chest; a valve box having alining openings in its top and bottom walls which lead directly into the action chest and to the atmosphere, respectively; a striker pneumatic secured to said chest and constantly communicating with the interior of the valve box; a single valve in said box to control both openings and thereby govern communication between the interiors of the box and chest; a fixed tube mounted in one wall of the chest and adapted for connection at its outer end with a tracker tube; and a collapsible and expansible pouch connected to the inner end of the fixed tube and disposed between said tube end and the valve to operate the latter consequent upon its expansion.

GUILLERMO FREUND. 

